Block copolymer formulation and methods relating thereto

ABSTRACT

A block copolymer formulation is provided including a block copolymer blend including a first poly(acrylate)-b-poly(silyl acrylate) block copolymer; and, a second poly(acrylate)-b-poly(silyl acrylate) block copolymer. Also provided are substrates treated with the block copolymer formulation.

The present invention relates to the field of self assembling blockcopolymers. In particular, the present invention is directed to a blockcopolymer formulation containing a block copolymer blend, including afirst poly(acrylate)-b-poly(silyl acrylate) block copolymer and a secondpoly(acrylate)-b-poly(silyl acrylate) diblock copolymer.

Some block copolymers, consisting of two or more distinct homopolymersjoined end to end, are known self-assemble into periodic micro domainshaving typical dimensions of 10 nanometers to 50 nanometers (nm). Thepossibility of using such micro domains to pattern surfaces hasattracted increasing interest because of the expense and difficulty ofpatterning in nanoscale dimensions (especially sub-45 nm) using opticallithography.

Controlling the lateral placement of the block copolymer micro domainson the substrates continues to be a challenge, however. This problem hasbeen previously addressed using lithographically pre-defined topographicand/or chemical patterning of the substrate. Previous studies havedemonstrated that self-assembled block copolymer micro domains in formof lamellae can be directed to follow chemical patterning of thesubstrate, yielding periodicities close to those of the chemicalpre-patterns. Other studies have shown that by controlling the surfacewetting properties of the block copolymer on the bottom and side wallsof a topographic pre-pattern, the lamellae can be directed to follow thetopographic pre-pattern. The lamellae formed line/space patterns ofsmaller dimensions than the substrate pre-pattern, subdividing thetopographic pre-pattern into a higher frequency line pattern; that is, aline pattern having a smaller pitch. One limitation of block copolymerpatterning is the propensity of the patterns to form everywhere on thepre-pattern surface, for topographic and/or chemical guidingpre-patterns.

The ability to shrink the size of various features on a given substrate(e.g., gates in field effect transistors) is currently limited by thewavelength of light used to expose photoresists (i.e., 193 nm). Theselimitations create a significant challenge for the fabrication offeatures having a critical dimension (CD) of <50 nm. The use ofconventional block copolymers present difficulties in orientationcontrol and long range ordering during the self assembly process.Moreover, such block copolymers frequently provide inadequate etchresistance for subsequent processing steps.

Takenaka, et al. ¹ investigated the use of diblock copolymer fordirected self assembly. Specifically, Takenaka, et al. demonstrated thedirected self assembly down to sub-10-nm half pitch using apoly(styrene)-b-poly(dimethyl siloxane) diblock copolymer with amolecular weight of 15.8 kg/mol; a heterogeneity index of 1.03; and, apoly(styrene) volume fraction of 0.74 poly(styrene); wherein the diblockcopolymer film was annealed in vacuum at 170° C. for 24 hours.¹Takenaka, et al, Formation of long-range stripe patterns with sub-10-nmhalf-pitch from directed self-assembly of block copolymer, JOURNAL OFPOLYMER SCIENCE: PART B, Polymer Physics, vol. 48, pp. 2297-2301 (2010).

Notwithstanding, there remains a need for new copolymer compositions foruse in patterning substrates. In particular, there remains a need fornew copolymer compositions that enable patterning on intermediate lengthscales (e.g., 20 to 40 nm) and that preferably exhibit a fast annealingprofile with low defect formation.

The present invention provides a block copolymer formulation,comprising: a block copolymer blend, comprising: a firstpoly(acylate)-b-poly(silyl acrylate) block copolymer (“DB1”) having aDB1 poly(acrylate) block, a DB1 poly(silyl acrylate) block and a DB1number average molecular weight, M_(N-DB1), of 10 to 1,000 kg/mol; a DB1polydispersity, PD_(DB1), of 1 to 3; and, a secondpoly(acrylate)-b-poly(silyl acrylate) block copolymer (“DB2”) having aDB2 poly(acrylate) block, a DB2 poly(silyl acrylate) block and a DB2number average molecular weight, M_(N-DB2), of 1 to 1,000 kg/mol; a DB2polydispersity, PD_(DB2), of 1 to 3; and, ≧2 wt % antioxidant (based onthe weight of the block copolymer blend).

The present invention provides a method comprising: providing asubstrate; providing a block copolymer formulation of the presentinvention; applying a film of the block copolymer formulation to thesubstrate; optionally, baking the film; annealing the film; treating theannealed film to remove the DB1 poly(acrylate) block and the DB2poly(acrylate) block from the annealed film and to convert the DB1poly(silyl acrylate) block and the DB2 poly(silyl acrylate) block in theannealed film to SiO_(x).

The present invention provides a block copolymer formulation,comprising: a block copolymer blend, comprising: a firstpoly(acylate)-b-poly(silyl acrylate) block copolymer (“DB1”) having aDB1 poly(acrylate) block, a DB1 poly(silyl acrylate) block and a DB1number average molecular weight, M_(N-DB1), of 10 to 1,000 kg/mol; a DB1polydispersity, PD_(DB1), of 1 to 3; and, a secondpoly(acrylate)-b-poly(silyl acrylate) block copolymer (“DB2”) having aDB2 poly(acrylate) block, a DB2 poly(silyl acrylate) block and a DB2number average molecular weight, M_(N-DB2), of 1 to 1,000 kg/mol; a DB2polydispersity, PD_(DB2), of 1 to 3; wherein the block copolymerformulation contains ≦75 wt % of a poly(methylmethacrylate)-block-poly((trimethylsilyl)methyl methacrylate) diblockcopolymer.

The present invention provides a block copolymer formulation,comprising: a block copolymer blend, comprising: a firstpoly(acylate)-b-poly(silyl acrylate) block copolymer (“DB1”) having aDB1 poly(acrylate) block, a DB1 poly(silyl acrylate) block and a DB1number average molecular weight, M_(N-DB1), of 10 to 1,000 kg/mol; a DB1polydispersity, PD_(DB1), of 1 to 3; and, a secondpoly(acrylate)-b-poly(silyl acrylate) block copolymer (“DB2”) having aDB2 poly(acrylate) block, a DB2 poly(silyl acrylate) block and a DB2number average molecular weight, M_(N-DB2), of 1 to 1,000 kg/mol; a DB2polydispersity, PD_(DB2), of 1 to 3; wherein the block copolymerformulation contains <0.001 wt % of a poly(methylmethacrylate)-block-poly((trimethylsilyl)methyl methacrylate) diblockcopolymer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a depiction of a top down scanning electron microscopic(“SEM”) image of the product film prepared according to Example 8.

FIG. 2 is a depiction of a top down scanning electron microscopic(“SEM”) image of the product film prepared according to Example 9.

DETAILED DESCRIPTION

When applied to the surface of a substrate, the block copolymerformulation of the present invention exhibits an improved capability toanneal at a given processing temperature to a low defect structurecompared to that obtained using a conventional silicon containingpolymers, such as PS-b-PDMS. Moreover, the incorporation of an inorganicmoiety in the poly(silyl acrylate) domains of the block copolymerformulation of the present invention is convertible to an etch resistantspecies (e.g., a mask) upon processing of the deposited block copolymerformulation to remove the organic components. The block copolymerformulation of the present invention provides significant value forenabling thermal processing in directed self assembly applications usedto form periodic nano structures, such as line/space patterns on siliconcontaining substrates, in, for example, the 20-40 nm range.

The term “PAcr-b-PSiAcr block copolymer” used herein and in the appendedclaims is short hand for a poly(acrylate)-block-poly(silyl acrylate);wherein the poly(acrylate) block includes residues from at least one ofan acrylate monomer, a deuterated acrylate monomer, an acrylate blockmodifying monomer and a deuterated acrylate block modifying monomer;and, wherein the poly(silyl acrylate) block includes residues from atleast one of a silyl acrylate monomer, a deuterated silyl acrylatemonomer, a silyl acrylate block modifying monomer and a deuterated silylacrylate block modifying monomer.

The term “deuterated acrylate monomer” used herein and in the appendedclaims is an acrylate monomer in which at least one hydrogen has beenreplaced with deuterium. The term “deuterated acrylate block modifyingmonomer” used herein and in the appended claims is an acrylate modifyingmonomer in which at least one hydrogen has been replaced with deuterium.

The term “deuterated silyl acrylate monomer” used herein and in theappended claims is a silyl acrylate monomer in which at least onehydrogen has been replaced with deuterium.

The term “deuterated silyl acrylate block modifying monomer” used hereinand in the appended claims is a silyl acrylate modifying monomer inwhich at least one hydrogen has been replaced with deuterium.

The terms “(trimethylsilyl)methyl methacrylate” and “TMSMMA” used hereinand in the appended claims refers to a monomer having the followingmolecular structure:

The term “PMMA-b-PTMSMMA block copolymer” used herein and in theappended claims is short hand for a poly(methylmethacrylate)-block-poly((trimethylsilyl)methyl methacrylate) blockcopolymer.

The term “M_(N-BCP)” used herein and in the appended claims in referenceto a poly(acrylate)-b-poly(silyl acrylate) block copolymer used in theblock copolymer formulation of the present invention is the numberaverage molecular weight of the poly(acrylate)-b-poly(silyl acrylate)block copolymer determined according to the method used herein in theExamples.

The term “M_(N-Blend) or blend number average molecular weight” usedherein and in the appended claims in reference to a block copolymerblend used in the block copolymer formulation of the present inventionis the weighted average of the number average molecular weights of thepoly(acrylate)-b-poly(silyl acrylate) block copolymers included in theblock copolymer blend.

The term “M_(W-BCP)” used herein and in the appended claims in referenceto a poly(acrylate)-b-poly(silyl acrylate) block copolymer used in theblock copolymer formulation of the present invention is the weightaverage molecular weight of the poly(acrylate)-b-poly(silyl acrylate)block copolymer determined according to the method used herein in theExamples.

The term “M_(W-Blend) or blend weight average molecular weight” usedherein and in the appended claims in reference to a block copolymerblend used in the block copolymer formulation of the present inventionis the weighted average of the weight average molecular weights of thepoly(acrylate)-b-poly(silyl acrylate) block copolymers included in theblock copolymer blend.

The term “PD_(BCP)” used herein and in the appended claims in referenceto a poly(acrylate)-b-poly(silyl acrylate) block copolymer used in theblock copolymer formulation of the present invention is thepolydispersity of the poly(acrylate)-b-poly(silyl acrylate) blockcopolymer determined according to the following equation:

${PD}_{BCP} = {\frac{M_{W - {BCP}}}{M_{N - {BCP}}}.}$

The term “Wf_(PAcr)” used herein and in the appended claims in referenceto a poly(acrylate)-b-poly(silyl acrylate) block copolymer used in theblock copolymer formulation of the present invention is the weightpercent of the poly(acrylate) block in the poly(acrylate)-b-poly(silylacrylate) block copolymer.

The term “Wf_(PAcr-Blend) or blend poly(acrylate) weight fraction” usedherein and in the appended claims in reference to a block copolymerblend used in the block copolymer formulation of the present inventionis the weighted average of the weight percent of the poly(acrylate)block in the poly(acrylate)-b-poly(silyl acrylate) block copolymersincluded in the block copolymer blend.

The term “Wf_(PSiAcr)” used herein and in the appended claims inreference to a poly(acrylate)-b-poly(silyl acrylate) block copolymerused in the block copolymer formulation of the present invention is theweight percent of the poly(silyl acrylate) block in thepoly(acrylate)-b-poly(silyl acrylate) block copolymer.

The term “Wf_(PSiAcr-Blend) or blend poly(silyl acrylate) weightfraction” used herein and in the appended claims in reference to a blockcopolymer blend used in the block copolymer formulation of the presentinvention is the weighted average of the weight percent of thepoly(silyl acrylate) block in the poly(acrylate)-b-poly(silyl acrylate)block copolymers included in the block copolymer blend.

Block copolymers are polymers that are synthesized from two or moredifferent monomers and exhibit two or more polymeric chain segments thatare chemically different, but yet, are covalently bound to one another.Diblock copolymers are a special class of block copolymers derived fromtwo different monomers (e.g., A and B) and having a structure comprisinga polymeric block of A residues covalently bound to a polymeric block ofB residues (e.g., AAAAA-BBBBB).

The poly(acrylate)-b-poly(silyl acrylate) block copolymers used in theblock copolymer formulation of the present invention include blockcopolymers having a poly(acrylate) block and a poly(silyl acrylate)block. The poly(acrylate)-b-poly(silyl acrylate) block copolymers usedin the block copolymer formulation of the present invention optionallycontain one or more other blocks (e.g., a triblock copolymer).

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention comprises domains of poly(acrylate)and poly(silyl acrylate); wherein the block copolymer formulationexhibits a film pitch, L₀, of 10 to 100 nm (preferably 14 to 60 nm; mostpreferably 20 to 40 nm) when deposited on a substrate under theconditions set forth herein in the Examples.

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention comprises: a firstpoly(acrylate)-b-poly(silyl acrylate) block copolymer (“DB1”) having aDB1 poly(acrylate) block, a DB1 poly(silyl acrylate) block, a DB1 numberaverage molecular weight, M_(N-DB1), of 10 to 1,000 kg/mol (preferably15 to 200 kg/mol; more preferably 15 to 100 kg/mol; most preferably 20to 60 kg/mol); a DB1 polydispersity, PD_(DB1), of 1 to 3 (preferably 1to 2; most preferably 1 to 1.2); and, a secondpoly(acrylate)-b-poly(silyl acrylate) block copolymer (“DB2”) having aDB2 poly(acrylate) block, a DB2 poly(silyl acrylate) block, a DB2 numberaverage molecular weight, M_(N-DB2), of 1 to 1,000 kg/mol (preferably 1to 300 kg/mol; more preferably 1 to 100 kg/mol; most preferably 20 to 60kg/mol); a DB2 polydispersity, PD_(DB2), of 1 to 3 (preferably 1 to 2;most preferably 1.2). Preferably, the block copolymer blend used in theblock copolymer formulation of the present invention includes a DB1 anda DB2, wherein the weight ratio of DB1 to DB2 in the block copolymerblend is 1:1 to 1:9 (preferably 1:1 to 1:5; more preferably 1:1 to1:2.5). More preferably, the block copolymer blend used in the blockcopolymer formulation of the present invention includes a DB1 and a DB2,wherein the block copolymer blend is ≧33 wt % to 99 wt % DB1 and 1 to≦50 wt % DB2 (preferably ≧50 to 99 wt % DB1 and 1 to ≦50 wt % DB2).

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention exhibits a blend poly(acrylate)weight fraction, Wf_(PAcr-Blend), in a range selected from the group ofranges consisting of 0.69 to 0.83 (preferably 0.69 to 0.80; mostpreferably 0.70 to 0.75); 0.39 to <0.69 (preferably 0.44 to 0.64; mostpreferably 0.49 to 0.59); and 0.23 to <0.39 (preferably 0.26 to 0.34;most preferably 0.27 to 0.30); and wherein the block copolymer blendexhibits a blend number average molecular weight, M_(N-Blend), of 10 to1,000 kg/mol (preferably 15 to 200 kg/mol; more preferably 15 to 100kg/mol; most preferably 20 to 60 kg/mol).

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention includes a blend ofpoly(acrylate)-b-poly(silyl acrylate) block copolymers having a blendpoly(acrylate) weight fraction, Wf_(PAcr-Blend), of 0.69 to 0.83(preferably 0.69 to 0.80; most preferably 0.70 to 0.75); and a blendnumber average molecular weight, M_(N-Blend), of 10 to 1,000 kg/mol(preferably 15 to 200 kg/mol; more preferably 15 to 100 kg/mol; mostpreferably 20 to 60 kg/mol). Block copolymer blends of the presentinvention having a Wf_(PAcr-Blend) of 0.69 to 0.83 and an M_(N-Blend) of10 to 1,000 kg/mol tend to exhibit cylindrical poly(silyl acrylate)domains that microphase separate from the poly(acrylate) domains. Giventhe teachings provided herein, one of ordinary skill in the art will beable to deposit a block copolymer formulation of the present inventioncontaining such a PAcr-b-PSiAcr block copolymer blend, whereincylindrical poly(silyl acrylate) domains in the deposited blockcopolymer formulation will self assemble to orient themselves with theiraxes of symmetry parallel to the surface of the substrate, perpendicularto the surface of the substrate or a combination of parallel andperpendicular to the surface of the substrate, through the selection andcontrol of the film deposition conditions, for example: (a) thesubstrate's surface energy (i.e., by pretreating the surface of thesubstrate with an interposing material), (b) the thickness of the filmof block copolymer formulation, (c) the bake profile of the depositedblock copolymer formulation (i.e., bake temperature and bake time) and(d) the anneal profile of the deposited block copolymer formulation(i.e., anneal temperature and anneal time).

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention includes a blend of PAcr-b-PSiAcrblock copolymers having a blend poly(acrylate) weight fraction,Wf_(PAcr-Blend), of 0.39 to <0.69 (preferably 0.44 to 0.64; mostpreferably 0.49 to 0.59); and a blend number average molecular weight,M_(N-Blend), of 10 to 1,000 kg/mol (preferably 15 to 200 kg/mol; morepreferably 15 to 100 kg/mol; most preferably 20 to 60 kg/mol). Blockcopolymer blends of the present invention having a Wf_(PAcr-Blend) of0.39 to <0.69 and an M_(N-Blend) of 10 to 1,000 kg/mol tend to exhibitmicrophase separated poly(acrylate) domains and poly(silyl acrylate)lamellar domains. Given the teachings provided herein, one of ordinaryskill in the art will be able to deposit a block copolymer formulationof the present invention containing such a PAcr-b-PSiAcr block copolymerblend, wherein lamellar domains in the deposited block copolymerformulation will self assemble to orient themselves with their axes ofsymmetry parallel to the surface of the substrate, perpendicular to thesurface of the substrate or a combination of parallel and perpendicularto the surface of the substrate, through the selection and control ofthe film deposition conditions, for example: (a) the substrate's surfaceenergy (i.e., by pretreating the surface of the substrate with aninterposing material), (b) the thickness of the film of block copolymerformulation deposited, (c) the bake profile of the deposited blockcopolymer formulation (i.e., bake temperature and bake time) and (d) theanneal profile of the deposited block copolymer formulation (i.e.,anneal temperature and anneal time).

Preferably, the block copolymer blend used in the block copolymerformulation of the present invention includes a blend of PAcr-b-PSiAcrblock copolymers having a blend poly(acrylate) weight fraction,Wf_(PAcr-Blend), of 0.23 to <0.39 (preferably 0.26 to 0.34; mostpreferably 0.27 to 0.30); and a blend number average molecular weight,M_(N-Blends) of 10 to 1,000 kg/mol (preferably 15 to 200 kg/mol; morepreferably 15 to 100 kg/mol; most preferably 20 to 60 kg/mol). Blockcopolymer blends of the present invention having a Wf_(PAcr-Blend) of0.23 to <0.39 and an M_(N-Blend) of 10 to 1,000 kg/mol tend to exhibitcylindrical poly(acrylate) domains that microphase separate from thepoly(silyl acrylate) domains. Given the teachings provided herein, oneof ordinary skill in the art will be able to deposit a block copolymerformulation of the present invention containing such a PAcr-b-PSiAcrblock copolymer blend, wherein cylindrical poly(acrylate) domains in thedeposited block copolymer formulation will self assemble to orientthemselves with their axes of symmetry parallel to the surface of thesubstrate, perpendicular to the surface of the substrate or acombination of parallel and perpendicular to the surface of thesubstrate, through the selection and control of the film depositionconditions, for example: (a) the substrate's surface energy (i.e., bypretreating the surface of the substrate with an interposing material),(b) the thickness of the film of block copolymer formulation deposited,(c) the bake profile of the deposited block copolymer formulation (i.e.,bake temperature and bake time) and (d) the anneal profile of thedeposited block copolymer formulation (i.e., anneal temperature andanneal time).

Preferably, the poly(acrylate)-b-poly(silyl acrylate) block copolymersused in the block copolymer formulation of the present invention have apoly(acrylate) block; wherein the poly(acrylate) block includes residuesfrom at least one of an acrylate monomer, a deuterated acrylate monomer,an acrylate block modifying monomer and a deuterated acrylate blockmodifying monomer; and, wherein the poly(acrylate) block includes >75 wt% (more preferably, >90 wt %; most preferably, >95 wt %) of acrylatemonomer derived units.

Preferably, the acrylate monomer is selected from the group consistingof aryl(alkyl)acrylate (e.g., phenyl acrylate, phenyl methacrylate);alkyl(alkyl)acrylate (e.g., methyl acrylate, methyl methacrylate);halogenated aryl(alkyl)acrylate (e.g., chlorophenyl acrylate,chlorophenyl methacrylate); halogenated alkyl(alkyl)acrylate (e.g.,fluoropropyl acrylate, fluoropropyl methacrylate) and, combinationsthereof. More preferably, the acrylate monomer is selected from thegroup consisting of C₆₋₁₄ aryl (C₁₋₅ alkyl)acrylate; C₁₋₅ alkyl (C₁₋₅alkyl)acrylate. Still more preferably, the acrylate monomer is selectedfrom the group consisting of butyl(meth)acrylate, propyl(meth)acrylate),ethyl(meth)acrylate, methyl(meth)acrylate. Most preferably, the acrylatemonomer is methyl methacrylate.

Preferably, the deuterated acrylate monomer is selected from the groupconsisting of deuterated aryl(alkyl)acrylate (e.g., deuterated phenylacrylate, deuterated phenyl methacrylate); deuteratedalkyl(alkyl)acrylate (e.g., deuterated methyl acrylate, deuteratedmethyl methacrylate); deuterated halogenated aryl(alkyl)acrylate (e.g.,deuterated chlorophenyl acrylate, deuterated chlorophenyl methacrylate);deuterated halogenated alkyl(alkyl)acrylate (e.g., deuteratedfluoropropyl acrylate, deuterated fluoropropyl methacrylate) and,combinations thereof. More preferably, the deuterated acrylate monomeris selected from the group consisting of deuterated C₆₋₁₄ aryl (C₁₋₅alkyl)acrylate; deuterated C₁₋₅ alkyl (C₁₋₅ alkyl)acrylate. Still morepreferably, the deuterated acrylate monomer is selected from the groupconsisting of deuterated butyl(meth)acrylate, deuteratedpropyl(meth)acrylate), deuterated ethyl(meth)acrylate, deuteratedmethyl(meth)acrylate. Most preferably, the deuterated acrylate monomeris deuterated methyl methacrylate.

Preferably, the acrylate block modifying monomer is selected from thegroup consisting of an alkene and a cycloalkene. More preferably, theacrylate block modifying monomer is selected from a C₁₋₅ alkene and aC₃₋₇ cycloalkene. Most preferably, the acrylate block modifying monomeris ethylene.

Preferably, the deuterated acrylate block modifying monomer is selectedfrom the group consisting of a deuterated alkene and a deuteratedcycloalkene. More preferably, the deuterated acrylate block modifyingmonomer is selected from a deuterated C₁₋₅ alkene and deuterated a C₃₋₇cycloalkene. Most preferably, the deuterated acrylate block modifyingmonomer is deuterated ethylene.

Preferably, the poly(acrylate)-b-poly(silyl acrylate) block copolymersused in the block copolymer formulation of the present invention have apoly(silyl acrylate) block; wherein the poly(silyl acrylate) blockincludes residues from at least one of a silyl acrylate monomer, adeuterated silyl acrylate monomer, a silyl acrylate block modifyingmonomer and a deuterated silyl acrylate block modifying monomer; and,wherein the poly(silyl acrylate) block includes >75 wt % (morepreferably, >90 wt %; most preferably, >95 wt %) of silyl acrylatemonomer derived units.

Preferably, the silyl acrylate monomer is according to the followingformula(R¹(R²)(R³)Si)_(r)R⁴ _(x)OOCC(R⁵)═CR⁶ ₂wherein each R¹, R² and R³ is independently selected from the groupconsisting of a C₁₋₁₈ alkyl group, a halogenated C₁₋₁₈ alkyl group, asilylated C₁₋₁₈ alkyl group, a silylated halogenated C₁₋₁₈ alkyl group,an oxy C₁₋₁₈ alkyl group, an oxy silylated C₁₋₁₈ alkyl group, an oxysilylated halogenated C₁₋₁₈ alkyl group, a C₆₋₁₄ aryl group, ahalogenated C₆₋₁₄ aryl group, an oxy C₆₋₁₄ aryl group, a silylated C₆₋₁₄aryl group, an oxy silylated C₆₋₁₄ aryl group, an oxy silylatedhalogenated C₆₋₁₄ aryl group, a C₁₋₁₈ arylalkyl group, a halogenatedC₁₋₁₈ arylalkyl group, an oxy C₁₋₁₈ arylalkyl group, a silylated C₁₋₁₈arylalkyl group, a silylated halogenated C₁₋₁₈ arylalkyl group, an oxysilylated C₁₋₁₈ arylalkyl group, an oxy silylated halogenated C₁₋₁₈arylalkyl group, a C₆₋₁₄ alkylaryl group, a halogenated C₆₋₁₄ alkylarylgroup, an oxy C₆₋₁₄ alkylaryl group, a silylated C₆₋₁₄ alkylaryl group,an oxy silylated C₆₋₁₄ alkylaryl group and an oxy silylated halogenatedC₆₋₁₄ alkylaryl group (preferably, a C₁₋₆ alkyl group, a silylated C₁₋₆alkyl group, an oxy C₁₋₆ alkyl group, an oxy silylated C₁₋₆ alkyl group,a C₆₋₁₀ aryl group, an oxy C₆₋₁₀ aryl group, a silylated C₆₋₁₀ arylgroup, an oxy silylated C₆₋₁₀ aryl group, a C₁₋₁₀ arylalkyl group, anoxy C₁₋₁₀ arylalkyl group, a silylated C₁₋₁₀ arylalkyl group, an oxysilylated C₁₋₁₀ arylalkyl group, a C₆₋₁₀ alkylaryl group, an oxy C₆₋₁₀alkylaryl group, a silylated C₆₋₁₀ alkylaryl group and an oxy silylatedC₆₋₁₀ alkylaryl group; more preferably, a C₁₋₃ alkyl group; mostpreferably, a methyl group); wherein r is selected from the groupconsisting of 0, 1, 2 and 3 (preferably, 1, 2 and 3; more preferably, ris 1); wherein R⁴ is selected from the group consisting of a C₁₋₁₀alkyl, a halogenated C₁₋₁₀ alkyl group, a silylated C₁₋₁₀ alkyl group, asilylated halogenated C₁₋₁₀ alkyl group, an oxy silylated C₁₋₁₀ alkylgroup and a halogenated oxy silylated C₁₋₁₀ alkyl group (preferably, aC₁₋₃ alkyl group and a halogenated C₁₋₃ alkyl group; more preferably, aC₁₋₃ alkyl group; most preferably a methyl group); wherein x is selectedfrom the group consisting of 0 and 1 (preferably, x is 1); wherein R⁵ isselected from the group consisting of a hydrogen, a halogen, a C₁₋₃alkyl group, a silylated C₁₋₃ alkyl group and a halogenated C₁₋₃ alkylgroup (preferably, a hydrogen and a methyl group; more preferably, amethyl group); wherein each R⁶ is independently selected from ahydrogen, a halogen, a silyl methyl group, a methyl group and ahalogenated methyl group (preferably, a hydrogen and a methyl group;more preferably, a hydrogen); and, wherein the silyl acrylate monomerincludes at least one Si atom. More preferably, the silyl acrylatemonomer is selected from the group consisting of(trimethylsilyl)methyl(meth)acrylate;(triethylsilyl)methyl(meth)acrylate;(tripropylsilyl)methyl(meth)acrylate;(triisopropylsilyl)methyl(meth)acrylate;(tributylsilyl)methyl(meth)acrylate;(tri-sec-butylsilyl)methyl(meth)acrylate;(triisobutylsilyl)methyl(meth)acrylate;(sec-butylmethylsilyl)methyl(meth)acrylate;(sec-butyldimethylsilyl)methyl(meth)acrylate;(dimethylpropylsilyl)methyl(meth)acrylate;(monomethyldipropylsilyl)methyl(meth)acrylate;(methylethylpropylsilyl)methyl(meth)acrylate;bis(trimethylsilyl)methyl(meth)acrylate;tris(trimethylsilyl)methyl(meth)acrylate;(pentamethyldisilyl)methyl(meth)acrylate;tris(trimethylsiloxy)methyl(meth)acrylate;tris(trimethylsiloxy)propyl(meth)acrylate);(pentamethyldisiloxy)methyl(meth)acrylate;(pentamethyldisiloxy)propyl(meth)acrylate;(trimethoxysilyl)propyl(meth)acrylate; and,(triethoxysilyl)propyl(meth)acrylate. Most preferably, the silylacrylate monomer is (trimethylsilyl)methyl methacrylate.

Preferably, the deuterated silyl acrylate monomer is according to thefollowing formula(R⁷(R⁸)(R⁹)Si)_(t)R¹⁰ _(y)OOCC(R¹¹)═CR¹² ₂wherein each R⁷, R⁸ and R⁹ is independently selected from a C₁₋₁₈ alkylgroup, a halogenated C₁₋₁₈ alkyl group, a silylated C₁₋₁₈ alkyl group, asilylated halogenated C₁₋₁₈ alkyl group, an oxy C₁₋₁₈ alkyl group, anoxy silylated C₁₋₁₈ alkyl group, an oxy silylated halogenated C₁₋₁₈alkyl group, a C₆₋₁₄ aryl group, a halogenated C₆₋₁₄ aryl group, an oxyC₆₋₁₄ aryl group, a silylated C₆₋₁₄ aryl group, an oxy silylated C₆₋₁₄aryl group, an oxy silylated halogenated C₆₋₁₄ aryl group, a C₁₋₁₈arylalkyl group, a halogenated C₁₋₁₈ arylalkyl group, an oxy C₁₋₁₈arylalkyl group, a silylated C₁₋₁₈ arylalkyl group, a silylatedhalogenated C₁₋₁₈ arylalkyl group, an oxy silylated C₁₋₁₈ arylalkylgroup, an oxy silylated halogenated C₁₋₁₈ arylalkyl group, a C₆₋₁₄alkylaryl group, a halogenated C₆₋₁₄ alkylaryl group, an oxy C₆₋₁₄alkylaryl group, a silylated C₆₋₁₄ alkylaryl group, an oxy silylatedC₆₋₁₄ alkylaryl group, an oxy silylated halogenated C₆₋₁₄ alkylarylgroup, a deuterated C₁₋₁₈ alkyl group, a deuterated halogenated C₁₋₁₈alkyl group, a deuterated silylated C₁₋₁₈ alkyl group, a deuteratedsilylated halogenated C₁₋₁₈ alkyl group, a deuterated oxy C₁₋₁₈ alkylgroup, a deuterated oxy silylated C₁₋₁₈ alkyl group, a deuterated oxysilylated halogenated C₁₋₁₈ alkyl group, a deuterated C₆₋₁₄ aryl group,a deuterated halogenated C₆₋₁₄ aryl group, a deuterated oxy C₆₋₁₄ arylgroup, a deuterated silylated C₆₋₁₄ aryl group, a deuterated oxysilylated C₆₋₁₄ aryl group, a deuterated oxy silylated halogenated C₆₋₁₄aryl group, a deuterated C₁₋₁₈ arylalkyl group, a deuterated halogenatedC₁₋₁₈ arylalkyl group, a deuterated oxy C₁₋₁₈ arylalkyl group, adeuterated silylated C₁₋₁₈ arylalkyl group, a deuterated silylatedhalogenated C₁₋₁₈ arylalkyl group, a deuterated oxy silylated C₁₋₁₈arylalkyl group, a deuterated oxy silylated halogenated C₁₋₁₈ arylalkylgroup, a deuterated C₆₋₁₄ alkylaryl group, a deuterated halogenatedC₆₋₁₄ alkylaryl group, a deuterated oxy C₆₋₁₄ alkylaryl group, adeuterated silylated C₆₋₁₄ alkylaryl group, a deuterated oxy silylatedC₆₋₁₄ alkylaryl group and a deuterated oxy silylated halogenated C₆₋₁₄alkylaryl group (preferably, a C₁₋₆ alkyl group, a silylated C₁₋₆ alkylgroup, an oxy C₁₋₆ alkyl group, an oxy silylated C₁₋₆ alkyl group, aC₆₋₁₀ aryl group, an oxy C₆₋₁₀ aryl group, a silylated C₆₋₁₀ aryl group,an oxy silylated C₆₋₁₀ aryl group, a C₁₋₁₀ arylalkyl group, an oxy C₁₋₁₀arylalkyl group, a silylated C₁₋₁₀ arylalkyl group, an oxy silylatedC₁₋₁₀ arylalkyl group, a C₆₋₁₀ alkylaryl group, an oxy C₆₋₁₀ alkylarylgroup, a silylated C₆₋₁₀ alkylaryl group, an oxy silylated C₆₋₁₀alkylaryl group, a deuterated C₁₋₆ alkyl group, a deuterated silylatedC₁₋₆ alkyl group, a deuterated oxy C₁₋₆ alkyl group, a deuterated oxysilylated C₁₋₆ alkyl group, a deuterated C₆₋₁₀ aryl group, a deuteratedoxy C₆₋₁₀ aryl group, a deuterated silylated C₆₋₁₀ aryl group, adeuterated oxy silylated C₆₋₁₀ aryl group, a deuterated C₁₋₁₀ arylalkylgroup, a deuterated oxy C₁₋₁₀ arylalkyl group, a deuterated silylatedC₁₋₁₀ arylalkyl group, a deuterated oxy silylated C₁₋₁₀ arylalkyl group,a deuterated C₆₋₁₀ alkylaryl group, a deuterated oxy C₆₋₁₀ alkylarylgroup, a deuterated silylated C₆₋₁₀ alkylaryl group and a deuterated oxysilylated C₆₋₁₀ alkylaryl group; more preferably, a C₁₋₃ alkyl group anda deuterated C₁₋₃ alkyl group; most preferably, a methyl group and adeuterated methyl group); wherein t is selected from the groupconsisting of 0, 1, 2 and 3 (preferably, 1, 2 and 3; more preferably, tis 1); wherein R¹⁰ is selected from the group consisting of a C₁₋₁₀alkyl, a halogenated C₁₋₁₀ alkyl group, a silylated C₁₋₁₀ alkyl group, asilylated halogenated C₁₋₁₀ alkyl group, an oxy silylated C₁₋₁₀ alkylgroup, a halogenated oxy silylated C₁₋₁₀ alkyl group, a deuterated C₁₋₁₀alkyl, a deuterated halogenated C₁₋₁₀ alkyl group, a deuteratedsilylated C₁₋₁₀ alkyl group, a deuterated silylated halogenated C₁₋₁₀alkyl group, a deuterated oxy silylated C₁₋₁₀ alkyl group and adeuterated halogenated oxy silylated C₁₋₁₀ alkyl group (preferably, aC₁₋₃ alkyl group and a deuterated C₁₋₃ alkyl group; more preferably, aC₁₋₃ alkyl group; most preferably a methyl group); wherein y is 0 or 1(preferably, y is 1); wherein R¹¹ is selected from the group consistingof a hydrogen, a deuterium, a halogen, a C₁₋₃ alkyl group, a deuteratedC₁₋₃ alkyl group, a silylated C₁₋₃ alkyl group, a deuterated silylatedC₁₋₃ alkyl group, a halogenated C₁₋₃ alkyl group and a deuteratedhalogenated C₁₋₃ alkyl group (preferably, a hydrogen, a deuterium, amethyl group and a deuterated methyl group; more preferably, a methylgroup); wherein each R¹² is independently selected from a hydrogen, adeuterium, a halogen, a silyl methyl group, a deuterated silyl methylgroup, a methyl group, a deuterated methyl group, a halogenated methylgroup and a deuterated halogenated methyl group (preferably, a hydrogen,a deuterium, a methyl group and a deuterated methyl group; morepreferably, a hydrogen); wherein the deuterated silyl acrylate monomercontains at least one Si atom; and, wherein the deuterated silylacrylate monomer contains at least one deuterium. More preferably, thedeuterated silyl acrylate monomer is selected from the group consistingof deuterated (trimethylsilyl)methyl(meth)acrylate; deuterated(triethylsilyl)methyl(meth)acrylate; deuterated(tripropylsilyl)methyl(meth)acrylate; deuterated(triisopropylsilyl)methyl(meth)acrylate; deuterated(tributylsilyl)methyl(meth)acrylate; deuterated(tri-sec-butylsilyl)methyl(meth)acrylate; deuterated(triisobutylsilyl)methyl(meth)acrylate; deuterated(sec-butylmethylsilyl)methyl(meth)acrylate; deuterated(sec-butyldimethylsilyl)methyl(meth)acrylate; deuterated(dimethylpropylsilyl)methyl(meth)acrylate; deuterated(monomethyldipropylsilyl)methyl(meth)acrylate; deuterated(methylethylpropylsilyl)methyl(meth)acrylate; deuteratedbis(trimethylsilyl)methyl(meth)acrylate; deuteratedtris(trimethylsilyl)methyl(meth)acrylate; deuterated(pentamethyldisilyl)methyl(meth)acrylate; deuteratedtris(trimethylsiloxy)methyl(meth)acrylate; deuteratedtris(trimethylsiloxy)propyl(meth)acrylate); deuterated(pentamethyldisiloxy)methyl(meth)acrylate; deuterated(pentamethyldisoloxy)propyl(meth)acrylate; deuterated(trimethoxysilyl)propyl(meth)acrylate; and, deuterated(triethoxysilyl)propyl(meth)acrylate. Most preferably, the deuteratedsilyl acrylate monomer is deuterated (trimethylsilyl)methylmethacrylate.

Preferably, the silyl acrylate block modifying monomer is selected fromthe group consisting of an alkene and a cycloalkene. More preferably,the silyl acrylate block modifying monomer is selected from a C₁₋₅alkene and a C₃₋₇ cycloalkene. Most preferably, the silyl acrylate blockmodifying monomer is ethylene.

Preferably, the deuterated silyl acrylate block modifying monomer isselected from the group consisting of a deuterated alkene and adeuterated cycloalkene. More preferably, the deuterated silyl acrylateblock modifying monomer is selected from a deuterated C₁₋₅ alkene anddeuterated a C₃₋₇ cycloalkene. Most preferably, the deuterated silylacrylate block modifying monomer is deuterated ethylene.

Preferably, the block copolymer formulation of the present inventioncontains ≧2 wt % antioxidant (based on the weight of the block copolymerblend). More preferably, the block copolymer formulation contains 2 to30 wt % antioxidant (based on the weight of the block copolymer blend).Still more preferably, the block copolymer formulation contains 5 to 30wt % antioxidant (based on the weight of the block copolymer blend).Still more preferably, the block copolymer formulation contains 10 to 25wt % antioxidant (based on the weight of the block copolymer blend).Most preferably, the block copolymer formulation contains 15 to 25 wt %antioxidant (based on the weight of the block copolymer blend).

Antioxidant contained in the block copolymer formulation of the presentinvention can be selected from primary antioxidants and secondaryantioxidants. Preferably, the antioxidant is selected from the groupconsisting of: antioxidants containing at least one (preferably at leasttwo; more preferably at least three; most preferably three to four)2,6-di-tert-butylphenol moiety; antioxidants containing at least one(preferably at least two; more preferably at least three; mostpreferably three to four) moiety according to the formula

antioxidants containing at least one (preferably at least two; mostpreferably two) moiety according to the formula

and,

antioxidants containing at least one (preferably at least two; mostpreferably two) moiety according to the formula

and,mixtures thereof. More preferably, the antioxidant is selected from thegroup consisting of:

mixtures thereof. Still more preferably, the antioxidant is selectedfrom the group consisting of

and mixtures of

and one or more other antioxidants. Most preferably, the antioxidant is

Preferably, the antioxidant (or mixture of antioxidants) contained inthe block copolymer formulation of the present invention has an averagemolecular weight of ≧358 g/mol. More preferably, the antioxidant (ormixture of antioxidants) contained in the block copolymer formulation ofthe present invention has an average molecular weight of ≧600 g/mol.Most preferably, the antioxidant (or mixture of antioxidants) containedin the block copolymer formulation of the present invention has anaverage molecular weight of ≧1,000 g/mol.

Preferably, the antioxidant (or mixture of antioxidants) contained inthe block copolymer formulation of the present invention has an averageboiling point temperature measured at 760 mm Hg (101.3 kPa) of >400° C.More preferably, the antioxidant (or mixture of antioxidants) containedin the block copolymer formulation of the present invention has anaverage boiling point temperature measured at 760 mm Hg (101.3 kPa)of >500° C. Still more preferably, the antioxidant (or mixture ofantioxidants) contained in the block copolymer formulation of thepresent invention has an average boiling point temperature measured at760 mm Hg (101.3 kPa) of >700° C. Yet still more preferably, theantioxidant (or mixture of antioxidants) contained in the blockcopolymer formulation of the present invention has an average boilingpoint temperature measured at 760 mm Hg (101.3 kPa) of >800° C. Mostpreferably, the antioxidant (or mixture of antioxidants) contained inthe block copolymer formulation of the present invention has an averageboiling point temperature measured at 760 mm Hg (101.3 kPa) of >1,000°C.

The block copolymer formulation of the present invention optionallyfurther comprises a solvent. Solvents include liquids that are able todisperse the block copolymers into particles or aggregates having anaverage hydrodynamic diameter of less than 50 mm as measured by dynamiclight scattering. Preferably, the solvent used is selected frompropylene glycol monomethyl ether acetate (PGMEA), ethoxyethylpropionate, anisole, ethyl lactate, 2-heptanone, cyclohexanone, amylacetate, γ-butyrolactone (GBL), n-methylpyrrolidone (NMP) and toluene.More preferably, the solvent used is selected from propylene glycolmonomethyl ether acetate (PGMEA) and toluene. Most preferably, thesolvent used is toluene.

The block copolymer formulation of the present invention optionallyfurther comprises an additive. Additives include additional polymers(including homopolymers and random copolymers); surfactants;antioxidants; photoacid generators; thermal acid generators; quenchers;hardeners; adhesion promoters; dissolution rate modifiers; photocuringagents; photosensitizers; acid amplifiers; plasticizers; orientationcontrol agents; and cross linking agents. Preferred additives for use inthe block copolymer formulation include homopolymers; surfactants andantioxidants.

Preferably, the block copolymer formulation of the present inventionfurther comprises a poly(acrylate) homopolymer additive (preferably apolymethyl methacrylate (“HPMMA”) homopolymer additive). Morepreferably, the block copolymer formulation of the present inventioncomprises a poly(acrylate) homopolymer (preferably HPMMA); wherein theweight ratio of the poly(acrylate) homopolymer to the block copolymerblend is 1:19 to 3:7 (preferably 1:9 to 3:7; more preferably 1:9 to1:4). The block copolymer formulation of the present inventionpreferably contains 5 to 30 wt % (more preferably 10 to 30 wt %; mostpreferably 10 to 20 wt %)(on a solids basis) of a poly(acrylate)homopolymer (preferably HPMMA). Preferred poly(acrylate) homopolymer hasa number average molecular weight, M_(N-HPAcr), of 1 to 100 kg/mol (morepreferably 5 to 50 kg/mol; most preferably 10 to 30 kg/mol). Morepreferably, the block copolymer formulation of the present inventionincludes a poly(acrylate) homopolymer (preferably HPMMA); wherein theweight ratio of the poly(acrylate) homopolymer to the block copolymerblend is 1:19 to 3:7 (preferably 1:9 to 3:7; more preferably 1:9 to1:4); wherein the weight ratio of DB1 to DB2 in the block copolymerblend is 1:1 to 1:2.5; wherein the weight fraction of the DB1poly(acrylate) block, Wf_(PAcr-DB1), is 0.7 to 0.75; wherein M_(N-DB1)is 20 to 60 kg/mol; wherein PD_(DB1) is 1. to 1.2; wherein the weightfraction of the DB2 poly(acrylate) block, Wf_(PAcr-DB2), is 0.7 to 0.75;wherein M_(N-DB2) is 20 to 60 kg/mol; and, wherein PD_(DB2) is 1. to1.2.

The method of the present invention preferably comprises: providing asubstrate; providing a block copolymer formulation of the presentinvention; applying a film of the block copolymer formulation to thesubstrate; optionally, baking the film; annealing the film; treating theannealed film to remove the poly(acrylate) domains from the annealedfilm and to convert the poly(silyl acrylate) domains in the annealedfilm to SiO_(x).

Substrates used in the method of the present invention include anysubstrate having a surface that can be coated with the block copolymerformulation of the present invention. Preferred substrates includelayered substrates. Preferred substrates include silicon containingsubstrates (e.g., glass; silicon dioxide; silicon nitride; siliconoxynitride; silicon containing semiconductor substrates such as siliconwafers, silicon wafer fragments, silicon on insulator substrates,silicon on sapphire substrates, epitaxial layers of silicon on a basesemiconductor foundation, silicon-germanium substrates); plastic; metals(e.g., copper, ruthenium, gold, platinum, aluminum, titanium andalloys); titanium nitride; and non-silicon containing semiconductivesubstrates (e.g., non-silicon containing wafer fragments, non-siliconcontaining wafers, germanium, gallium arsenide and indium phosphide).Most preferred substrates are silicon containing substrates.

Optionally, the surface of the substrate to be coated with the blockcopolymer formulation of the present invention is pretreated with aninterposing material before the block copolymer formulation of thepresent invention is applied. Preferably, the pretreatment material actslike a tying layer interposed between the surface of the substrate andthe block copolymers in the block copolymer formulation of the presentinvention to enhance the adhesion between the block copolymers and thesubstrate. Preferably, the interposing material forms a layer selectedfrom an imaging layer and an orientation control layer.

Imaging layers suitable for use in the method of the present inventioninclude, for example, any type of material that can be patterned orselectively activated. Such materials include, for example, polymerbrushes and a self-assembled monolayers of silane and siloxanecompounds.

Orientation control layers suitable for use in the method of the presentinvention include neutral and non-neutral orientation control layers.That is, the orientation control layer can form an interface between thesurface of the substrate and the block copolymers in the block copolymerformulation of the present invention that is preferentially wetted byone of the poly(acrylate) domains or the poly(silyl acrylate)domains—i.e., a non-neutral orientation control layer. A neutralorientation control layer refers to a layer that forms an interfacebetween the surface of the substrate and the block copolymers in theblock copolymer formulation of the present invention that is equallywetted by both the poly(acrylate) domains and the poly(silyl acrylate)domains. Neutral orientation control layers preferably include filmsprepared by casting a random copolymer that comprises residues of bothacrylate monomers and silyl acrylate monomers (e.g., poly(methylmethacrylate)-r-(trimethylsilyl)methyl methacrylate)-OH).

Preferably, the pretreatment of the substrate before depositing theblock copolymer formulation of the present invention is performed tofacilitate the guided self assembly of the block copolymers in the blockcopolymer formulation. Specifically, the pretreatment can facilitate oneof the two conventional methods used for guided self assembly of blockcopolymer films, namely graphoepitaxy and chemical epitaxy. In thegraphoepitaxy, the surface of the substrate is prepatterned withtopographical features on the surface of substrate (e.g., trenches,holes) that operate to direct the self organization of the blocks in theblock copolymer.

In the chemical epitaxy, the surface of the substrate is treated with afilm that exhibits a compositional pattern, wherein the affinity betweenthe various parts of the compositional pattern is different for thepoly(acrylate) domains and the poly(silyl acrylate) domains. Thischemical affinity difference operates to facilitate the directed selfassembly of the block copolymer formulation.

Preferably, the interposing layer is formed on the substrate using amethod selected from spin coating, dip coating, roll coating, spraycoating and laminating (most preferably spin coating). After applicationof the interposing layer forming material onto the surface of thesubstrate, the material is optionally further processed to remove anyresidual solvent. Preferably, the interposing layer is baked at anelevated temperature (e.g., 70 to 340° C.) for at least 10 seconds to 5minutes to remove any residual solvent from the interposing layer.Preferably, the baked interposing layer is rinsed with a solvent capableof removing any residual unbound interposing layer material from thesurface of the substrate and then rebaked at an elevated temperature(e.g., 70 to 340° C.) for at least 10 seconds to 5 minutes to remove anyresidual solvent.

Applying a film of the block copolymer formulation of the presentinvention to the substrate in the method of the present inventionpreferably comprises depositing the block copolymer formulation onto thesubstrate using a method selected from spin coating, dip coating, rollcoating, spray coating and laminating (most preferably spin coating).After application of the block copolymer formulation to the substrate,the deposited block copolymer formulation is optionally furtherprocessed to remove any residual solvent. Preferably, the depositedblock copolymer formulation is baked at an elevated temperature (e.g.,70 to 340° C.) for at least 10 seconds to 5 minutes to remove anyresidual solvent from the deposited film of the block copolymerformulation.

Annealing of the deposited film can be done by any annealing technique,for example, thermal annealing, thermal gradient annealing and solventvapor annealing. Preferably, the film is annealed using a thermalannealing technique. More preferably, the deposited film is annealedusing a thermal annealing technique, wherein the deposited film isheated at a temperature of 200 to 340° C. (more preferably 200 to 300°C.; most preferably 225 to 300° C.) for a period of 0.5 minute to 2 days(more preferably 0.5 minute to 2 hours; still more preferably 0.5 minuteto 0.5 hour; most preferably 0.5 minute to 5 minutes). Preferably, thedeposited film is annealed using a thermal annealing technique under agaseous atmosphere, wherein the gaseous atmosphere is selected from anatmosphere containing ≧20 wt % oxygen and an atmosphere containing <20wt % oxygen. More preferably, the deposited film is thermally annealedunder a gaseous atmosphere, wherein the gaseous atmosphere is selectedfrom a gaseous nitrogen atmosphere and a gaseous argon atmosphere,wherein the gaseous atmosphere has an oxygen concentration of ≦150 ppm(more preferably, ≦10 ppm; still more preferably, ≦7.5 ppm; yet stillmore preferably, ≦6.5 ppm; most preferably, ≦5 ppm). Most preferably,the deposited film is thermally annealed under a gaseous nitrogenatmosphere having an oxygen concentration of ≦100 ppm (preferably, ≦7.5ppm; more preferably, ≦6.5 ppm; most preferably, ≦5 ppm).

In the method of the present invention, the annealed film is treated toremove the poly(acrylate) domains in the annealed film and to convertthe poly(silyl acrylate) domains in the annealed film to SiO_(x),providing a product film with a plurality of voids (i.e., trench shapedvoids perpendicular to the surface of the substrate; cylindrical holeswith axes of symmetry perpendicular to the surface of the substrate; aplurality of cylindrical SiO_(x) posts with axes of symmetryperpendicular to the surface of the substrate). The treatment comprises:exposing the film to conditions that exhibit differential reactivitytowards the poly(acrylate) domains in the film relative to thepoly(silyl acrylate) domains in the film, to facilitate removal of thepoly(acrylate) domains from the annealed film and the conversion of thepoly(silyl acrylate) domains to SiO_(x). Preferably, the treatmentcomprises: optionally, exposing the annealed film to a halogencontaining plasma (e.g., CF₄) to remove any wetting layer that formed onthe surface of the annealed film; followed by exposing the annealed filmto a reactive plasma or a reactive ion etching atmosphere to remove thepoly(acrylate) domains and to convert the poly(silyl acrylate) domainsto SiO_(x). Most preferably, the treatment comprises: exposing theannealed film to a halogen containing plasma to remove any wetting layerformed on the annealed film; and then exposing the annealed film to areactive plasma or a reactive ion etching atmosphere, wherein theatmosphere comprises a plasma composed of a low pressure ionizedoxidizing gas (preferably O₂); wherein the poly(acrylate) domains in theannealed film is removed and the poly(silyl acrylate) domains in theannealed film is converted to SiO_(x).

Some embodiments of the present invention will now be described indetail in the following Examples.

The following materials were passed through a column packed withactivated A-2 grade alumina before being used in the Examples herein,namely tetrahydrofuran (99.9% pure available from Aldrich), styrene(available from Aldrich), and cyclohexane (HPCL grade available fromFischer). The following materials were passed through a column packedwith basic alumina before being used in the Examples herein, namely1,1-diphenylethylene (available from Aldrich) and methyl methacrylate(MMA). All the other materials used in the Examples herein werecommercial materials that were used as received.

The film thicknesses reported in the Examples herein were measured usinga NanoSpec/AFT 2100 Film Thickness Measurement tool. The thickness ofthe films were determined from the interference of a white light passedthrough a diffraction grating. A standard program called “Polyimide onSilicon” was used to analyze the component wavelengths (380-780 nm) todetermine the film thickness. The thickness of the film of the depositedblock copolymer formulation and the brush layer were measured togetheras one polymeric layer. The reported film thickness is the combinedthickness of the deposited block copolymer formulation and the brushlayer.

The number average molecular weight, M_(N), and polydispersity valuesreported in the Examples were measured by gel permeation chromatography(GPC) on an Agilent 1100 series LC system equipped with an Agilent 1100series refractive index and MiniDAWN light scattering detector (WyattTechnology Co.). Samples were dissolved in HPCL grade THF at aconcentration of approximately 1 mg/mL and filtered through at 0.20 μmsyringe filter before injection through the two PLGel 300×7.5 mm Mixed Ccolumns (5 mm, Polymer Laboratories, Inc.). A flow rate of 1 mL/min andtemperature of 35° C. were maintained. The columns were calibrated withnarrow molecular weight PS standards (EasiCal PS-2, PolymerLaboratories, Inc.).

Proton nuclear magnetic resonance (¹H NMR) spectroscopy results referredto in the Examples was done on a Varian INOVA 400 MHz NMR spectrometer.Deuterated chloroform was used. A delay time of 10 seconds was used toensure complete relaxation of protons for quantitative integrations.Chemical shifts are reported relative to tetramethylsilane.

A PlasmaTherm 790i/ reactive ion etch platform was used for all of thereactive ion etching steps mentioned in the Examples.

The film pitch, L₀, for the films reported in the Examples was measuredusing image analysis of the SEMS of the films with ImageJ, a publicdomain, JAVA based image processing program. Spatial calibration wasfirst carried out to convert distance in pixels in the image todistances in nanometers for a given SEM image. To measure the filmpitch, a line was drawn across and perpendicular to multiple SiO_(x)cylinders. The film pitch was calculated by dividing the length of thedrawn line by (n−1), wherein n is the number of SiO_(x) cylinderscrossed by the drawn line.

Example 1 Preparation of Hydroxyl-Terminated Polystyrene Brush

Into a 2 liter glass reactor under a nitrogen atmosphere was addedcyclohexane (1,500 g). Styrene (50.34 g) was then added to the reactorvia cannula. The contents of the reactor were then heated to 40° C.Sec-butyllithium (19.18 g) diluted in cyclohexane to a concentration of0.32 M was then rapidly added to the reactor via cannula, causing thereactor contents to turn yellow. The contents of the reactor werestirred for 30 minutes. The contents of the reactor were then cooled to30° C. Ethylene oxide (0.73 g) was then transferred into the reactor.The contents of the reactor were stirred for 15 minutes. Then a 20 mL ofa 1.4 M solution of HCl in methanol was added to the reactor. Thepolymer in the reactor was then isolated by precipitating intoisopropanol at a ratio of 500 mL of polymer solution to 1,250 mL ofisopropanol. The resulting precipitate was then filtered and driedovernight in a vacuum oven at 60° C., yielding 42 g of producthydroxyl-terminated polystyrene. The product hydroxyl-terminatedpolystyrene exhibited a number average molecular weight, M_(N), of 7.4kg/mol and a polydispersity, PD, of 1.07.

Example 2 Preparation PMMA-b-PTMSMMA Diblock Copolymer

Into a 500 mL 3-neck round bottom reactor under an argon atmosphere wasadded tetrahydrofuran (“THF”)(226 g). The THF was then cooled in thereactor to −78° C. The contents of the reactor were then titrated with a0.36 M solution of sec-butyllithium in cyclohexane until the contents ofthe reactor exhibited a persistent pale yellow color. The contents ofthe reactor were then warmed to, and maintained at, 30° C. until thecolor of the contents completely disappeared (approximately 10-15minutes). 1,1-diphenyl ethylene (0.110 g) diluted in cyclohexane (14.308g) was then transferred to the reactor via cannula. The contents of thereactor were then cooled to −78° C. Sec-butyllithium (0.62 g) dilutedwith cyclohexane to concentration of 0.60 M was then rapidly added tothe reactor via cannula, causing the reactor contents to turn a darkruby red. The reactor contents were allowed to stir for 15 minutes. Thenmethyl methacrylate (11.8 g) in cyclohexane (8.22 g) was transferred tothe reactor via cannula, causing the color of the reactor contents todisappear. The reactor contents exhibited a 15° C. temperature risewithin 1 minute of the addition of the methyl methacrylate to thereactor. The contents of the reactor then cooled back down to −78° C.and the reactor contents were stirred for an additional 55 minutes. Asmall portion of the reactor contents was then withdrawn for gelpermeation chromatography analysis of the polymethyl methacrylate(“PMMA”) block formed. (Trimethylsilyl)methyl methacrylate (“TMSMMA”)(4.54 g) diluted in cyclohexane (6.94 g) was then transferred into thereactor via cannula. Within 2 minutes of the addition of the TMSMMA tothe reactor, the reactor contents warmed to −74° C. before cooling backdown to −78° C. The reactor contents were stirred for an additional 2.5hours, after which the reaction was quenched by the addition ofanhydrous methanol to the reactor. The reactor contents were thenprecipitated into 1 liter of methanol. The product solids were collectedby vacuum filtration. After washing with additional methanol, thepolymer was redissolved in 150 mL of methylene chloride, washed twicewith deionized water and then reprecipitated into 1 liter of methanol.The polymer was then filtered and dried overnight in a vacuum oven at60° C., yielding 14.7 g. The product poly(methylmethacrylate)-b-poly(trimethylsilyl)methyl methacrylate block copolymer(“BCP1”) exhibited a weight average molecular weight, M_(W), of 41.5kg/mol; a polydispersity, PD, of 1.19 and a 29.7 wt %poly(trimethylsilyl)methyl methacrylate content (as determined by ¹HNMR).

Example 3 Preparation PMMA-b-PTMSMMA Diblock Copolymer

Into a 500 mL 3-neck round bottom reactor under an argon atmosphere wasadded tetrahydrofuran (“THF”)(198 g). The THF was then cooled in thereactor to −78° C. The contents of the reactor were then titrated with a0.36 M solution of sec-butyllithium in cyclohexane until the contents ofthe reactor exhibited a persistent pale yellow color. The contents ofthe reactor were then warmed to, and maintained at, 30° C. until thecolor of the contents completely disappeared (approximately 10-15minutes). 1,1-diphenylethylene (0.135 g) diluted in cyclohexane (5.099g) was then transferred to the reactor via cannula. The contents of thereactor were then cooled to −78° C. Sec-butyllithium (0.92 g) dilutedwith cyclohexane to concentration of 0.60 M was then rapidly added tothe reactor via cannula, causing the reactor contents to turn a darkruby red. The reactor contents were allowed to stir for 10 minutes. Thenmethyl methacrylate (11.85 g) in cyclohexane (11.99 g) was transferredto the reactor via cannula, causing the color of the reactor contents todisappear. The reactor contents exhibited a 17° C. temperature risewithin 1 minute of the addition of the methyl methacrylate to thereactor. The contents of the reactor then cooled back down to −78° C.and the reactor contents were stirred for an additional 60 minutes. Asmall portion of the reactor contents was then withdrawn for gelpermeation chromatography analysis of the polymethyl methacrylate(“PMMA”) block formed. (Trimethylsilyl)methyl methacrylate (“TMSMMA”)(4.53 g) diluted in cyclohexane (8.41 g) was then transferred into thereactor via cannula. Within 2 minutes of the addition of the TMSMMA tothe reactor, the reactor contents warmed to −71° C. before cooling backdown to −78° C. The reactor contents were stirred for an additional 2.1hours, after which the reaction was quenched by the addition ofanhydrous methanol to the reactor. The reactor contents were thenprecipitated into 1 liter of methanol. The product solids were collectedby vacuum filtration. After washing with additional methanol, thepolymer was redissolved in 150 mL of methylene chloride, washed twicewith deionized water and then reprecipitated into 1 liter of methanol.The polymer was then filtered and dried overnight in a vacuum oven at60° C., yielding 14.4 g. The product poly(methylmethacrylate)-b-poly(trimethylsilyl)methyl methacrylate block copolymer(“BCP2”) exhibited a weight average molecular weight, M_(W), of 32.6kg/mol; a polydispersity, PD, of 1.22 and a 29.2 wt %poly(trimethylsilyl)methyl methacrylate content (as determined by ¹HNMR).

Example 4 PMMA-b-PTMSMMA Diblock Copolymer Filtering

Each of the PMMA-b-PTMSMMA diblock copolymers prepared according toExample 2-3 was added to toluene to form a 2.0 wt % solution. The 2.0 wt% solutions formed were then separately hand filtered through a 0.2 μmWhatman syringe filter. The product filtrate material was collected forsubsequent use.

Example 5 Preparation of Block Copolymer Blend

The product filtrate of Example 4 obtained from the PMMA-b-PTMSMMAdiblock copolymer of Example 2, BCP1, and the product filtrate ofExample 4 obtained from the PMMA-b-PTMSMMA diblock copolymer of Example3, BCP2, were combined to form a BCP1:BCP2 weight ratio of 1:1. Apoly(methyl methacrylate) homopolymer (H-PMMA) having a number averagemolecular weight of 15 kg/mol (from Scientific Polymer Products, Inc.,catalog #424) was then added to the diblock copolymer blend to form theproduct block copolymer formulation having an H-PMMA:diblock copolymerblend weight ratio of 1:9. The product block copolymer blend wasprovided as 2 wt % solids in toluene; wherein the solids were blend of10 wt % H-PMMA; 45 wt % BCP1 and 45 wt % BCP2.

Example 6 Preparation of Block Copolymer Blend w/ Homopolymer

The product filtrate of Example 4 obtained from the PMMA-b-PTMSMMAdiblock copolymer of Example 2, BCP1, and the product filtrate ofExample 4 obtained from the PMMA-b-PTMSMMA diblock copolymer of Example3, BCP2, were combined to form a BCP1:BCP2 weight ratio of 1:1. Apoly(methyl methacrylate) homopolymer (H-PMMA) having a number averagemolecular weight of 15 kg/mol (from Scientific Polymer Products, Inc.,catalog #424) was then added to the diblock copolymer blend to form theproduct block copolymer blend with homopolymer having an H-PMMA:diblockcopolymer blend weight ratio of 1:4. The product block copolymer blendwith homopolymer was provided as 2 wt % solids in toluene; wherein thesolids were blend of 20 wt % H-PMMA; 40 wt % BCP1 and 40 wt % BCP2.

Example 7 Substrate Preparation

Substrates were prepared by cutting pieces (˜1″×1″) from a silicon waferhaving a native oxide layer. A hydroxyl-terminated polystyrene brushprepared according to Example 1 was dissolved in toluene to form 1.5 wt% brush solution. The brush solution was then spin coated onto eachsubstrate at 3,000 rpm for 1 minute. The deposited brush layer was thenbaked by placing the substrate onto a hotplate set at 150° C. for 1minute. The deposited brush layer was then annealed by placing thesubstrate onto another hotplate set at 250° C. for 20 minutes in anitrogen atmosphere. The substrate was then cooled to room temperature.The substrate was then immersed in toluene for 1 minute. The substratewas then spun dry at 3,000 rpm for 1 minute. The substrate was thenplaced on a hotplate set at 110° C. for 1 minute and then stored innitrogen until used.

Example 8 Film Deposition

A block copolymer composition prepared according to Example 5 was thenspin coated onto the polystyrene brushed surface of a substrate preparedaccording to Example 7 to form a 59 nm film. The substrate was thenplaced on a hotplate set at 150° C. for 1 minute to bake the film. Thesubstrate was then placed on another hotplate set at 270° C. under 25psig nitrogen atmosphere for 1 hour.

A surface wetting layer of PTMSMMA formed on the annealed film at theatmosphere-film interface. The annealed films were then treated usingtwo consecutive reactive ion etching (RIE) steps to reveal the blockcopolymer morphology of the deposited PMMA-b-PTMSMMA film. First, ashort CF₄ plasma (10 mT, 50 W) RIE treatment (8 seconds post plasmastabilization) was used to punch through the surface wetting layer ofPTMSMMA. Then, an O₂ plasma RIE treatment (25 seconds post plasmastabilization) was employed to remove the poly(methyl methacrylate)domains and converting the PTMSMMA domains to SiO_(x).

The plasma treated product film was then examined by Scanning ElectronMicroscopy using a Hitachi S-4500 scanning electron microscope (SEM)with a secondary electron detector. The test sample was mounted on theSEM stage using double sided carbon tape and cleaned by blowing nitrogenprior to analysis. An image of the test sample was collected at 50,000×magnification and working distances between 4 and 8. A top down image ofthe product film is provided in FIG. 1.

Example 9 Film Deposition

A block copolymer composition prepared according to Example 6 was thenspin coated onto the polystyrene brushed surface of a substrate preparedaccording to Example 7 to form a 57.5 nm film. The substrate was thenplaced on a hotplate set at 150° C. for 1 minute to bake the film. Thesubstrate was then placed on another hotplate set at 270° C. under 25psig nitrogen atmosphere for 1 hour.

A surface wetting layer of PTMSMMA formed on the annealed film at theatmosphere-film interface. The annealed films were then treated usingtwo consecutive reactive ion etching (RIE) steps to reveal the blockcopolymer morphology of the deposited PMMA-b-PTMSMMA film. First, ashort CF₄ plasma (10 mT, 50 W) RIE treatment (8 seconds post plasmastabilization) was used to punch through the surface wetting layer ofPTMSMMA. Then, an O₂ plasma RIE treatment (25 seconds post plasmastabilization) was employed to remove the poly(methyl methacrylate)domains and converting the PTMSMMA domains to SiO_(x).

The plasma treated product film was then examined by Scanning ElectronMicroscopy using a Hitachi S-4500 scanning electron microscope (SEM)with a secondary electron detector. The test sample was mounted on theSEM stage using double sided carbon tape and cleaned by blowing nitrogenprior to analysis. An image of the test sample was collected at 50,000×magnification and working distances between 4 and 8. A top down image ofthe product film is provided in FIG. 2.

Example 10 Preparation of Block Copolymer Formulation

The product filtrate of Example 4 obtained from the PMMA-b-PTMSMMAdiblock copolymer of Example 2, BCP1, and the product filtrate ofExample 4 obtained from the PMMA-b-PTMSMMA diblock copolymer of Example3, BCP2, are combined to form a BCP1:BCP2 weight ratio of 1:1. Apoly(methyl methacrylate) homopolymer (H-PMMA) having a number averagemolecular weight of 15 kg/mol (from Scientific Polymer Products, Inc.,catalog #424) is then added to the diblock copolymer blend to form ablock copolymer blend with homopolymer having an H-PMMA:diblockcopolymer blend weight ratio of 1:9.

Pentaerythritoltetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate) (availablefrom BASF under the tradename IRGANOX® 1010) is then added to thisformulation to form a block copolymer formulation with 5 wt % IRGANOX®1010. The product block copolymer formulation is then provided as 2 wt %solids in toluene; wherein the solids are a blend of 9.5 wt % H-PMMA;42.75 wt % BCP1 and 42.75 wt % BCP2, and 5 wt % IRGANOX® 1010.

Example 11 Film Deposition

A block copolymer formulation prepared according to Example 10 is spincoated onto a polystyrene brushed surface of a substrate preparedaccording to Example 7 to form a film. The substrate is then placed on ahotplate set at 150° C. for 1 minute to bake the film. The substrate isthen placed on another hotplate set at 270° C. under 25 psig nitrogenatmosphere for 1 hour.

A surface wetting layer of PTMSMMA forms at the atmosphere-filminterface of the annealed film. The annealed film is then treated usingtwo consecutive reactive ion etching (RIE) steps to reveal the blockcopolymer morphology of the deposited PMMA-b-PTMSMMA film. First, ashort CF₄ plasma (10 mT, 50 W) RIE treatment (8 seconds post plasmastabilization) is used to punch through the surface wetting layer ofPTMSMMA. Then, an O₂ plasma RIE treatment (25 seconds post plasmastabilization) is employed to remove the poly(methyl methacrylate)domains and convert the PTMSMMA domains to SiO_(x).

The plasma treated product film is then examined by Scanning ElectronMicroscopy An image of the test sample is collected at 50,000×magnification and working distances between 4 and 8. A top down image ofthe product film will display a fingerprint morphology consistent with acylindrical morphology oriented parallel to the substrate.

We claim:
 1. A block copolymer formulation, comprising: a blockcopolymer blend, comprising: a first poly(acylate)-b-poly(silylacrylate) block copolymer (“DB1”) having a DB1 poly(acrylate) block, aDB1 poly(silyl acrylate) block and a DB1 number average molecularweight, M_(N-DB1), of 10 to 1,000 kg/mol; a DB1 polydispersity,PD_(DB1), of 1 to 3; and, a second poly(acrylate)-b-poly(silyl acrylate)block copolymer (“DB2”) having a DB2 poly(acrylate) block, a DB2poly(silyl acrylate) block and a DB2 number average molecular weight,M_(N-DB2), of 1 to 1,000 kg/mol; a DB2 polydispersity, PD_(DB2), of 1 to3; and, ≧2 wt % antioxidant (based on the weight of the block copolymerblend).
 2. The block copolymer formulation of claim 1, wherein the blockcopolymer formulation contains 5 to 30 wt % antioxidant (based on theweight of the block copolymer blend).
 3. The block copolymer formulationof claim 1, wherein the weight ratio of DB1 to DB2 in the blockcopolymer blend is 1:1 to 1:9.
 4. The block copolymer formulation ofclaim 3, wherein the block copolymer blend is ≧33 wt % to 99 wt % DB1and 1 to ≦50 wt % DB2.
 5. The block copolymer formulation of claim 1,wherein the antioxidant is selected from the group consisting of: anantioxidant containing at least one 2,6-di-tert-butylphenol moiety; anantioxidant containing at least one moiety according to the formula

an antioxidant containing at least one moiety according to the formula

an antioxidants containing at least one moiety according to the formula

mixtures thereof.
 6. The block copolymer formulation of claim 1, whereinthe antioxidant is selected from the group consisting of

mixtures thereof.
 7. The block copolymer formulation of claim 1, whereinthe DB1 poly(acrylate) block and the DB2 poly(acrylate) block bothinclude residues from at least one of an acrylate monomer, a deuteratedacrylate monomer, an acrylate block modifying monomer and a deuteratedacrylate block modifying monomer; wherein the DB1 poly(acrylate) blockand the DB2 poly(acrylate) block both include >75 wt % of acrylatemonomer derived units; wherein the acrylate monomer is selected from thegroup consisting of C₆₋₁₄ aryl (C₁₋₅ alkyl)acrylate; C₁₋₅ alkyl (C₁₋₅alkyl)acrylate; wherein the deuterated acrylate monomer is selected fromthe group consisting of deuterated C₆₋₁₄ aryl (C₁₋₅ alkyl)acrylate;deuterated C₁₋₅ alkyl (C₁₋₅ alkyl)acrylate; wherein the acrylate blockmodifying monomer is selected from the group consisting of a C₁₋₅ alkeneand a C₃₋₇ cycloalkene; wherein the deuterated acrylate block modifyingmonomer is selected from a deuterated C₁₋₅ alkene and deuterated a C₃₋₇cycloalkene; and, wherein the DB1 poly(silyl acrylate) block and the DB2poly(silyl acrylate) block both include residues from at least one of asilyl acrylate monomer, a deuterated silyl acrylate monomer, a silylacrylate block modifying monomer and a deuterated silyl acrylate blockmodifying monomer; wherein the DB1 poly(silyl acrylate) block and theDB2 poly(silyl acrylate) block both include >75 wt % of silyl acrylatemonomer derived units; wherein the silyl acrylate monomer is accordingto the following formula(R¹(R²)(R³)Si)_(r)R⁴ _(x)OOCC(R⁵)═CR⁶ ₂ wherein each R¹, R² and R³ isindependently selected from the group consisting of a C₁₋₆ alkyl group,a silylated C₁₋₆ alkyl group, an oxy C₁₋₆ alkyl group, an oxy silylatedC₁₋₆ alkyl group, a C₆₋₁₀ aryl group, an oxy C₆₋₁₀ aryl group, asilylated C₆₋₁₀ aryl group, an oxy silylated C₆₋₁₀ aryl group, a C₁₋₁₀arylalkyl group, an oxy C₁₋₁₀ arylalkyl group, a silylated C₁₋₁₀arylalkyl group, an oxy silylated C₁₋₁₀ arylalkyl group, a C₆₋₁₀alkylaryl group, an oxy C₆₋₁₀ alkylaryl group, a silylated C₆₋₁₀alkylaryl group, an oxy silylated C₆₋₁₀ alkylaryl group; wherein r isselected from the group consisting of 0, 1, 2 and 3; wherein R⁴ isselected from the group consisting of a C₁₋₃ alkyl; wherein x isselected from the group consisting of 0 and 1; wherein R⁵ is selectedfrom the group consisting of a hydrogen and a methyl group; wherein eachR⁶ is a hydrogen; wherein the silyl acrylate monomer includes at leastone Si atom; wherein the deuterated silyl acrylate monomer is accordingto the following formula(R⁷(R⁸)(R⁹)Si)_(t)R¹⁰ _(y)OOCC(R¹¹)═CR¹² ₂ wherein each R⁷, R⁸ and R⁹ isindependently selected from a C₁₋₆ alkyl group, a silylated C₁₋₆ alkylgroup, an oxy C₁₋₆ alkyl group, an oxy silylated C₁₋₆ alkyl group, aC₆₋₁₀ aryl group, an oxy C₆₋₁₀ aryl group, a silylated C₆₋₁₀ aryl group,an oxy silylated C₆₋₁₀ aryl group, a C₁₋₁₀ arylalkyl group, an oxy C₁₋₁₀arylalkyl group, a silylated C₁₋₁₀ arylalkyl group, an oxy silylatedC₁₋₁₀ arylalkyl group, a C₆₋₁₀ alkylaryl group, an oxy C₆₋₁₀ alkylarylgroup, a silylated C₆₋₁₀ alkylaryl group, an oxy silylated C₆₋₁₀alkylaryl group, a deuterated C₁₋₆ alkyl group, a deuterated silylatedC₁₋₆ alkyl group, a deuterated oxy C₁₋₆ alkyl group, a deuterated oxysilylated C₁₋₆ alkyl group, a deuterated C₆₋₁₀ aryl group, a deuteratedoxy C₆₋₁₀ aryl group, a deuterated silylated C₆₋₁₀ aryl group, adeuterated oxy silylated C₆₋₁₀ aryl group, a deuterated C₁₋₁₀ arylalkylgroup, a deuterated oxy C₁₋₁₀ arylalkyl group, a deuterated silylatedarylalkyl group, a deuterated oxy silylated arylalkyl group, adeuterated C₆₋₁₀ alkylaryl group, a deuterated oxy C₆₋₁₀ alkylarylgroup, a deuterated silylated C₆₋₁₀ alkylaryl group and a deuterated oxysilylated C₆₋₁₀ alkylaryl group; wherein t is selected from the groupconsisting of 0, 1, 2 and 3; wherein R¹⁰ is selected from the groupconsisting of a C₁₋₃ alkyl group, and a deuterated C₁₋₃ alkyl; wherein yis 0 or 1; wherein R¹¹ is selected from the group consisting of ahydrogen, a deuterium, a methyl group and a deuterated methyl group;wherein each R¹² is selected from a hydrogen and a deuterium; whereinthe deuterated silyl acrylate monomer contains at least one Si atom;and, wherein the deuterated silyl acrylate monomer contains at least onedeuterium; wherein the silyl acrylate block modifying monomer isselected from the group consisting of an alkene and a cycloalkene; and,wherein the deuterated silyl acrylate block modifying monomer isselected from the group consisting of a deuterated alkene and adeuterated cycloalkene.
 8. The block copolymer formulation of claim 7,wherein the acrylate monomer is selected from the group consisting ofbutyl(meth)acrylate, propyl(meth)acrylate), ethyl(meth)acrylate,methyl(meth)acrylate; wherein the deuterated acrylate monomer isselected from the group consisting of deuterated butyl(meth)acrylate,deuterated propyl(meth)acrylate), deuterated ethyl(meth)acrylate,deuterated methyl(meth)acrylate; wherein the acrylate block modifyingmonomer is ethylene; and, wherein the deuterated acrylate blockmodifying monomer is deuterated ethylene; and, wherein the silylacrylate monomer is selected from the group consisting of(trimethylsilyl)methyl(meth)acrylate,(triethylsilyl)methyl(meth)acrylate,(tripropylsilyl)methyl(meth)acrylate,(triisopropylsilyl)methyl(meth)acrylate,(tributylsilyl)methyl(meth)acrylate,(tri-sec-butylsilyl)methyl(meth)acrylate,(triisobutylsilyl)methyl(meth)acrylate,(sec-butylmethylsilyl)methyl(meth)acrylate,(sec-butyldimethylsilyl)methyl(meth)acrylate,(dimethylpropylsilyl)methyl(meth)acrylate,(monomethyldipropylsilyl)methyl(meth)acrylate,(methylethylpropylsilyl)methyl(meth)acrylate,bis(trimethylsilyl)methyl(meth)acrylate,tris(trimethylsilyl)methyl(meth)acrylate,(pentamethyldisilyl)methyl(meth)acrylate,tris(trimethylsiloxy)methyl(meth)acrylate,tris(trimethylsiloxy)propyl(meth)acrylate),(pentamethyldisiloxy)methyl(meth)acrylate,(pentamethyldisiloxy)propyl(meth)acrylate,(trimethoxysilyl)propyl(meth)acrylate and(triethoxysilyl)propyl(meth)acrylate; wherein the deuterated silylacrylate monomer is selected from the group consisting of deuterated(trimethylsilyl)methyl(meth)acrylate, deuterated(triethylsilyl)methyl(meth)acrylate, deuterated(tripropylsilyl)methyl(meth)acrylate, deuterated(triisopropylsilyl)methyl(meth)acrylate, deuterated(tributylsilyl)methyl(meth)acrylate, deuterated(tri-sec-butylsilyl)methyl(meth)acrylate, deuterated(triisobutylsilyl)methyl(meth)acrylate, deuterated(sec-butylmethylsilyl)methyl(meth)acrylate, deuterated(sec-butyldimethylsilyl)methyl(meth)acrylate, deuterated(dimethylpropylsilyl)methyl(meth)acrylate, deuterated(monomethyldipropylsilyl)methyl(meth)acrylate, deuterated(methylethylpropylsilyl)methyl(meth)acrylate, deuteratedbis(trimethylsilyl)methyl(meth)acrylate, deuteratedtris(trimethylsilyl)methyl(meth)acrylate, deuterated(pentamethyldisilyl)methyl(meth)acrylate, deuteratedtris(trimethylsiloxy)methyl(meth)acrylate, deuteratedtris(trimethylsiloxy)propyl(meth)acrylate), deuterated(pentamethyldisiloxy)methyl(meth)acrylate, deuterated(pentamethyldisoloxy)propyl(meth)acrylate, deuterated(trimethoxysilyl)propyl(meth)acrylate and deuterated(triethoxysilyl)propyl(meth)acrylate; wherein silyl acrylate blockmodifying monomer is ethylene; and, wherein the deuterated silylacrylate block modifying monomer is selected from a deuterated ethylene.9. The block copolymer formulation of claim 8, further comprising apoly(methyl methacrylate) homopolymer (“HPMMA”), wherein the weightratio of the poly(methyl methacrylate) homopolymer (“HPMMA”) to theblock copolymer blend is 1:9 to 1:4; wherein the weight ratio of DB1 toDB2 is 1:1 to 1:2.5; wherein the weight fraction of the DB1poly(acrylate) block in DB1, Wf_(PAcr-DB1), is 0.7 to 0.75; whereinM_(N-DB1) is 20 to 60 kg/mol; wherein PD_(DB1) is
 1. to 1.2; wherein theweight fraction of the DB1 poly(acrylate) block in DB2, Wf_(PAcr-DB2),is 0.7 to 0.75; wherein M_(N-DB2) is 20 to 60 kg/mol; wherein PD_(DB2)is
 1. to 1.2; wherein the acrylate monomer is methyl(meth)acrylate; and,wherein the silyl acrylate monomer is(trimethylsilyl)methyl(meth)acrylate.
 10. A method comprising: providinga substrate; providing a block copolymer formulation according to claim1; applying a film of the block copolymer formulation to the substrate;optionally, baking the film; annealing the film; treating the annealedfilm to remove the DB1 poly(acrylate) block and the DB2 poly(acrylate)block from the annealed film and to convert the DB1 poly(silyl acrylate)block and the DB2 poly(silyl acrylate) block in the annealed film toSiO_(x).
 11. A block copolymer formulation, comprising: a blockcopolymer blend, comprising: a first poly(acylate)-b-poly(silylacrylate) block copolymer (“DB1”) having a DB1 poly(acrylate) block, aDB1 poly(silyl acrylate) block and a DB1 number average molecularweight, M_(N-DB1), of 10 to 1,000 kg/mol; a DB1 polydispersity,PD_(DB1), of 1 to 3; and, a second poly(acrylate)-b-poly(silyl acrylate)block copolymer (“DB2”) having a DB2 poly(acrylate) block, a DB2poly(silyl acrylate) block and a DB2 number average molecular weight,M_(N-DB2), of 1 to 1,000 kg/mol; a DB2 polydispersity, PD_(DB2), of 1 to3; wherein the block copolymer formulation contains ≦75 wt % of apoly(methyl methacrylate)-block-poly((trimethylsilyl)methylmethacrylate) diblock copolymer.
 12. The block copolymer formulation ofclaim 11, wherein the block copolymer formulation contains <0.001 wt %of a poly(methyl methacrylate)-block-poly((trimethylsilyl)methylmethacrylate) diblock copolymer.